Resistance training, sometimes known as weight training or strength training, is a specialized method of conditioning designed to increase muscle strength, muscle endurance, and muscle power. Resistance training refers to the use of any one or a combination of training methods which may include resistance machines, dumbbells, barbells, body weight, and rubber tubing.
The goal of resistance training, according to the American Sports Medicine Institute (ASMI), is to “gradually and progressively overload the musculoskeletal system so it gets stronger.” This is accomplished by exerting effort against a specific opposing force generated by elastic resistance (i.e. resistance to being stretched or bent). Exercises are isotonic if a body part is moving against the force. Exercises are isometric if a body part is holding still against the force. Resistance exercise is used to develop the strength and size of skeletal muscles. Full range of motion is important in resistance training because muscle overload occurs only at the specific joint angles where the muscle is worked. Properly performed, resistance training can provide significant functional benefits and improvement in overall health and well-being.
Research shows that regular resistance training will strengthen and tone muscles and increase bone mass. Resistance training should not be confused with weightlifting, power lifting or bodybuilding, which are competitive sports involving different types of strength training with non-elastic forces such as gravity (weight training or plyometrics) an immovable resistance (isometrics, usually the body's own muscles or a structural feature such as a door frame).
Whether or not increased strength is an objective, repetitive resistance training can also be utilized to elevate aerobic metabolism, for the purpose of weight loss.
Resistance exercise equipment has therefore developed into a popular tool used for conditioning, strength training, muscle building, and weight loss. Various types of resistance exercise equipment are known, such as free weights, exercise machines, and resistance exercise bands or tubing. Various limitations exist with the prior art exercise devices. For example, many types of exercise equipment, such as free weights and most exercise machines, are not portable. With respect to exercise bands and tubing, they may need to be attached to a stationary object, such as a closed door or a heavy piece of furniture, and require sufficient space. This becomes a problem when, for example, the user wishes to perform resistance exercises in a location where such stationary objects or sufficient space are not readily found. Resistance bands are also limited to a single resistance profile in which the amount of resistance changes as a function of angular displacement of the joint under load.
A need therefore exists for resistance exercise equipment that is portable, that may be used on its own without the need to employ other types of equipment, and that allows for adjustable resistance modes and levels.